As part of a nationwide quality improvement program, the standardised mortality ratio (SMR) of your Intensive Care Unit was compared to other similar Intensive Care Units using a funnel plot.
You are ICU “A” (filled red dot)
- a) What does the graph show about your ICU “A”? (20% marks)
- b) Explain how the SMR is calculated. (20% marks)
- c) Give the causes of an increased SMR. (60% marks)
Answer and interpretation
a) What does the graph show about your ICU “A”? (20% marks)
The SMR of ICU A is above the upper 99% CI indicating the SMR is significantly higher than similar
hospitals. Your ICU has significantly more deaths than expected compared to similar hospitals.
The overall SMR for the group is less than 1 and the SMR for ICU A is less than 1
b) Explain how the SMR is calculated. (20% marks)
SMR = O/E
O= observed number of deaths, E = expected number of deaths
E is derived from the average of the sample/ population.
Usually a risk adjustment model is used to calculate and account for severity of illness.
c) Give the causes of an increased SMR. (60% marks)
- Can be “apparent” or “real”.
- Data quality
- Incomplete or errors in data submission causing underestimated expected risk
- Widely different casemix of this ICU compared to others.
- Statistical model (risk adjustment) may no longer well calibrated
- True increase in mortality which can be due to
- i. Factors internal to ICU: very high occupancy, poor processes,, inadequate staffing
- ii. Factors external to ICU; problems in services that are high users of ICU e.g. surgery, system
- Pass rate: 27%
- Highest mark: 6.5
Additional Examiners’ Comments:
- Many candidates showed a significant knowledge gap relating to this commonly used quality indicator with insufficient details and structure in their answers.
Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also a Clinical Adjunct Associate Professor at Monash University. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.
After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.
He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE. He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of litfl.com, the RAGE podcast, the Resuscitology course, and the SMACC conference.
His one great achievement is being the father of three amazing children.
On Twitter, he is @precordialthump.